Irrational antibiotic use, inappropriate prescribing practices and unjustified self-medication continue to drive the emergence of antimicrobial resistance (AMR). The rapid rise and spread of resistant microorganisms in Pediatric Intensive Care Units (PICUs) is now a critical concern. This study aimed to evaluate the pattern of antibiotic resistance in the Pediatric Cardiac Intensive Care Unit (PCICU) of Bangladesh Shishu (Children) Hospital & Institute from January 2023 to December 2024. 

Children with cardiac diseases referred from across the country and admitted during the study period were enrolled. Blood, urine and tracheal aspirate samples were collected upon clinical suspicion of infection. Patients were monitored and outcomes recorded. During the study period, a total of 786 patients were admitted, nearly all of whom had received broad-spectrum antibiotics like third-generation cephalosporins (33.5%), carbapenems (20%), piperacillin (3.5%), and colistin (10%) prior to admission.

Pathogens were isolated in 12.5% of cases, with the majority being gram-negative bacteria: Acinetobacter (40%), Klebsiella (20.4%) and Pseudomonas (23.5%). Among Acinetobacter isolates, 89.7% were multidrug-resistant (MDR), and 10.3% were pan-drug-resistant. Alarmingly, 50% of Acinetobacter isolates were resistant to colistin, and 82% to carbapenems. Klebsiella, Pseudomonas, and E. coli also showed high resistance to commonly used antibiotics, particularly piperacillin and carbapenems. Staphylococcus species demonstrated 100% resistance to ampicillin and 66.7% resistance to gentamicin, ceftazidime and ceftriaxone.

Mortality was significantly higher among patients infected with MDR organisms (p<0.05). Particularly concerning is the emergence of Acinetobacter strains resistant to all available antibiotics, including colistin and carbapenems highlighting the real and present danger of pan-drug resistance, where no effective treatment options remain. Implementing antimicrobial stewardship is essential to combat resistance and reduce associated mortality.